Thread: Employee compensation for new accounts

We have an employee, our manager, who is capable of bringing lots of new business to the company. He has lots of contacts in the local community and is the type of person that people love to work with. Bottom line is he knows his stuff, has endless contacts, and the charm that could bring lots of new business to the company. How should he be compensated for new accounts he brings on board though? A one time payment or say an indefinite 5% of account gross revenue, 10%, 25%??? Cant find any guidelines for this, any and all help is greatly appreciated.